Range. - South Pacific, from southern California southward, breeding on the small islands on both coasts of Lower California. They are similar to the Leach's Petrel except that the rump is blackish. Data. - San Benito Is., Lower California, July 23, 1896. White egg laid on bare ground at the end of three foot burrow. Size 1.40 x 1. Collector, A. W. Anthony.